How We Got From OBD To OBD2

OBD is the standard vehicle diagnostic system used in the majority of cars and other light-duty vehicles. It allows the vehicle to monitor its health, self-diagnose issues, and report them. These reports provide information about the vehicle’s performance that can assist in analyzing repair needs.

Volkswagen introduced the first onboard computer system in 1968 in the fuel-injected Type 3. However, this system was completely analog and did not have any diagnostic capabilities. The first true OBD system – albeit rudimentary and non-standardized – was used on the Datsun 280Z in 1978. 

In 1979, the Society of Automotive Engineers (formerly the SAE, now known as SAE International) recommended the implementation of a more standardized OBD system with readable test signals for all passenger vehicles. It wasn’t until 1988 that the organization took the next step of recommending a standard controller and standardized set of codes. 

Then, in 1991, California was the first to codify these recommendations into regulations – the state required all vehicles to have an onboard diagnostic system. This first system was known as OBD1, and was often written with the Roman numeral as “OBDI.”

Over the next several years, the SAE updated the standardized designs of OBD equipment. In 1994, California mandated that all vehicles in the state would be required to feature this equipment. By 1996, new federal regulations required all vehicles to have this technology, which was now known as OBD2, or OBDII.

OBD2 protocols have continued to evolve incrementally since then, but OBD2 remains the standard today. This is why the equipment for reading these ports is often referred to as an OBD2 scanner.

a man holds up the connector for an obd2 scanner

OBD2 Scanners Have Become More Accessible

Auto technicians use OBD2 scanners to help diagnose issues with vehicles. But OBD2 scanners aren’t just for professionals. You can now find many affordable, yet very capable consumer-grade scanners to use for yourself.

While professional tools can cost thousands of dollars, the cost of a personal OBD2 scanner typically ranges from $20 to $500. Cheaper scanners do the basic job of reading and reporting vehicle codes but lack the features and convenience of pricier models. OBD2 scanners in the $40 range and above can provide more detailed information, offer enhanced connectivity over Bluetooth, and read more diagnostic information beyond error codes.

According to Will Moore of the product review team, most car owners can get the features they need with a model in the $40 range.

“Unless you are a serious mechanic, you’ll only need an OBD2 scanner that can read and clear engine codes,” said Moore. “The ability to run an I/M [inspection and maintenance] readiness check and scan ABS [anti-lock braking] systems can also be useful, even to the layperson. These features are all common among $40 OBD2 scanners.”

An OBD2 Scanner Can Tell You A Lot – But Not Everything

As electronic control modules (ECMs), sensors, and other monitoring technologies evolve, OBD2 scanners continue to provide increasingly precise information about a growing number of components. Onboard diagnostics systems such as the ECM use a system of standardized codes to report issues to an OBD2 scanner. Each code signifies a different error within the vehicle.

These codes can provide much more specific information than a general warning light on the dash panel. For example, if the “check engine” light illuminates in your instrument cluster, that doesn’t tell you much about what’s going on under the hood. However, if you plug in an OBD2 scanner to read the system, you might get the error code “P0201.” This code lets you know that there is an injector circuit malfunction and that the malfunction is in cylinder 1 of the engine block.

an obd2 scanner and its box sit on a beige car seat

But while an OBD2 scanner can tell you with impressive precision what is going on with your vehicle, it can’t necessarily tell you why it is happening. And perhaps more importantly, it can’t tell you exactly how to fix it. That’s why C.C. Haug, auto technician and owner of Good Judy Garage in Sheridan, Colorado, says the readings from OBD2 scanners are most useful as a jumping-off point.

“Digital control systems have made high-quality OEM-grade scan tools essential in a shop,” she said. “The generic OBD2 codes are a useful starting point in the hands of someone trained in diagnostics.”

Haug said that while these codes provide useful information for car owners and mechanics, there is often more to a problem than what can be read from a scanner.

“Let us take the example of the dreaded P0420 code,” explained Haug. “It doesn’t simply guarantee that the catalytic converter is bad. Someone trained in diagnostics will know that the general health of the engine and other control systems can cause this. So, it’s important to evaluate that.”

Even with the code in hand, said Haug, a good mechanic will still evaluate all possible reasons for the code to make sure they’re prescribing the right fix for the issue.

“You still need to check for vacuum and exhaust leaks, misfires – all of those things,” she said. “Data streaming oxygen sensor readings, checking learned fuel trims, and other things are essential before arriving at a decision that the converter is actually bad.”

Can An OBD2 Scanner Help You Get A Fair Estimate?

While an OBD2 scanner can’t do the job of a properly-trained mechanic, it can give you enough information to have a better idea of whether or not you’re getting an honest estimate at the shop. In this way, you can think of it as a research tool.

Before taking your car in for repairs, you can use an OBD2 scanner to learn more about any potential problems with your vehicle. Some scanners translate these codes into plain English – or in some cases, other languages – while other models will require you to look the code up online. This will provide a summary-level assessment of issues your vehicle may be experiencing. 

You can use what you learn from the scanner to get an estimated range of what fixing your issues is likely to cost. Sites like RepairPal aggregate user-reported data about repair costs for specific makes, models, and model years. If you drive a relatively popular vehicle, you should be able to find an estimated cost range for repairs. 

Once a trained technician takes a look, there is bound to be some difference between what you estimated with information from your OBD2 scanner and the actual quote. Yet while a technician might vary slightly on their assessment, the estimate you get shouldn’t vary too far from the information you found online. Unless the technician notices additional problems or the needed repairs are more substantial than the error codes would suggest, a quote that varies wildly from your own estimated costs could indicate that the shop is trying to sell you more than you need.

the obd2 port under the steering wheel in a car

It is important to remember that you can’t learn everything from an OBD2 scanner reading. There are also a lot of factors that go into estimating repair costs. Labor rates can vary based on location, and even within that location from shop to shop. Some shops may use more expensive parts than others. Also, technicians may vary in how they fix a specific problem.

In short, just because a repair estimate is higher than what you expected based on your research and an OBD2 reading, that doesn’t mean a shop is trying to pull a fast one on you. It does mean, however, that it’s probably worth shopping around a bit to get a second or third opinion.

OBD2 Scanners Can Make The Repair Process Easier For All

You don’t need to wait until you get an estimate from a shop to spring it on them that you, in fact, have an OBD2 scanner and have researched your vehicle’s issues. Providing error codes upfront when you make an appointment or bring your car in can signal to a shop that you know at least a little about what is going on. In many cases, said Haug, doing so can also be helpful to the shop and technicians.

“Our shop operates on an appointment-only basis at this point,” said Haug. “When a customer contacts us to schedule an appointment, any information they can provide helps us schedule the most appropriate appointment possible for them.”

Haug advised that while you can use an OBD2 scanner to turn off the often-annoying warning lights that accompany internal error codes, it’s best to leave them in place for a repair technician. 

“We recommend to customers that they don’t clear codes,” confirmed Haug. “Our technicians are trained to not rely on codes provided by customers during a diagnostic.”

Yes, an OBD2 scanner can indeed give you the information you need to spot a ripoff estimate when you see one. Armed with your own realistic estimate, you can avoid a mechanic who may overcharge you or sell you services you don’t need. But on the flip side is the fact that this information can also help you identify shops you can trust. If an estimate more or less lines up with what you learn from your scanner and cost research, it’s a good sign that the shop will treat you fairly now and in the future.

Electronic diagnostics systems and OBD2 scanners are inexpensive tools that can help car owners save money on repairs and learn more about their vehicles. They have also become essential in any auto shop and have helped improve the efficiency and efficacy of car repairs. 

But no matter how precise or in-depth these tools become, they’ll never be a full substitute for a skilled, knowledgeable, and diligent technician – like those who are certified by the National Institute for Automotive Service Excellence (ASE). As electronic diagnostic and reporting technology becomes more advanced and more integrated into vehicles, Haug says that she has some concerns about how much the industry has started to depend on that technology.

“I’m a bit old school, and in general I often feel like the industry as a whole has started to rely on scanner diagnostics a bit too much,” concluded Haug. “I also think the vehicle manufacturers have leaned into that, noting that the service manual diagnostics for a lot of the newer vehicles often omit a great deal of traditional circuit and component testing information. I worry that younger technicians don’t see the value in developing their electrical diagnostic skills.”

For now, electronic diagnostic systems OBD2 scanners are still a technology that helps mechanics, rather than takes their place. With reliable consumer-grade models at around $40 or less, they are also affordable tools that can help car owners avoid overpaying for repairs and find a mechanic they trust.


By admin